Section 4: Obtaining Profile Data
The next step in preparing the profile is to obtain the data you will use to address the
scope of the profile and answer the epidemiologic questions.
As the profile writer, you need to be aware of several considerations concerning the
acquisition and use of data to describe the epidemic in a service area. You also need
to know what types of data are available and where to obtain them.
This section presents a general discussion of those considerations—the types of
available data and where to find them—as preparation for Chapter 3, where these
issues are applied to the specific core epidemiologic questions.
General Data Considerations
The following are considerations for reviewing data and data sources that you may use
in the epidemiologic profile:
- Completeness of the data: How well does the number of
reported HIV or AIDS cases reflect the true number of persons who
have HIV infection or AIDS and are thus eligible to be reported? For
example, how well does the prevalence of AIDS represent the true
number of persons living with AIDS in your service area?
- Representativeness of the data: How well do the characteristics from a data
source correspond to the characteristics of the overall population? For example,
data from a hospital-based sample may not represent all HIV-infected persons or
all HIV-infected persons in care in the area covered by the survey.
- Age of the data: How old are the data that will be used for analysis? For
example, a behavioral survey conducted in 1990 might not provide data that are
sufficiently up-to-date for current prevention activities.
- Timeliness of the data: How long is the reporting delay between the diagnosis of
HIV or AIDS and the report to the health department?
- Limitations of the data source or variable of interest: Consider the limitations
of the data source or variable. For example, AIDS case data are the only HIVrelated
data that are consistently available on a population-wide basis in all states
by sex, race/ethnicity, age, and mode of HIV exposure. However, AIDS case data
may not reflect the characteristics of people who were recently infected with HIV.
- Surrogate, or proxy, markers: A proxy variable is used as a marker for other
variables when what we really want to measure is too difficult to measure directly.
For example, some areas may use sexually transmitted disease (STD) data as a
proxy when data on sexual behaviors are not available.
- Validity of the data: How well does a variable measure what it is intended to
measure? For example, how well was information about age transcribed to the
case report from the medical record (how accurate are the case report data
compared with those in the medical record)?
- Small numbers: You may need technical assistance to interpret the data when
analyzing small numbers of cases because small absolute changes in the number of
cases can produce large relative or proportionate changes in rates that may be
misinterpreted by end users. These analyses may also require the use of advanced
statistical tests. Rates calculated from numerators smaller than 20 should be
denoted in a footnote as unreliable.
Types and Sources of Data for Epidemiologic Profiles
This section includes a description of commonly available data and their sources.
Several of these sources directly report HIV and AIDS cases and clinical conditions of
persons with a diagnosis of HIV infection or AIDS. Other sources are used to round
out the picture of the HIV/AIDS epidemic in your service area. Other sources also are
used if no HIV incidence data are available. See Appendix A for an expanded list of
core and supplemental data sources and references.
| Type of Data
|
Description |
Where to Obtain |
| AIDS
surveillance |
AIDS reporting began in 1981, and AIDS is
a reportable condition in all states and
territories. The AIDS surveillance system
was established to
- monitor incidence and the demographic
profile of AIDS
- describe the modes of HIV transmission
among persons with AIDS
- guide the development and
implementation of public health
intervention and prevention programs
- assist in the evaluation of the efficacy of
public health interventions
State and local health departments actively
solicit disease reports from health care
providers, laboratories, and other sources.
Standardized case report forms are used to
collect sociodemographic information, mode
of exposure, testing history, and clinical
information. AIDS surveillance has been
determined to be more than 85% complete. |
All 50 states, the District of
Columbia, and US territories
collect AIDS surveillance data.
Contact your state or local
service area’s HIV/AIDS
surveillance coordinator. |
| HIV
surveillance |
HIV surveillance data include all persons
who meet the 1999 case definition for HIV
infection and have been reported to a state
or local health department. HIV Surveillance Data
- provide a minimum estimate of the
number of persons with a diagnosis of
HIV infection whose test was
confidential
- identify emerging patterns of
transmission
- help detect trends in HIV infections
among populations of particular interest
(e.g., children, adolescents, women)
that may not be evident from AIDS
surveillance data
HIV surveillance data also provide a basis
for establishing and evaluating linkages to
the provision of prevention and early
intervention services. They can be used to
anticipate unmet needs for HIV care.
According to state evaluations, HIV infection
reporting is estimated to be 80%–90%
complete for persons who have tested
positive for HIV. |
As of January 2004, 34 states
(Alabama, Alaska, Arizona,
Arkansas, Colorado, Florida,
Georgia, Idaho, Indiana, Iowa, Kansas, Louisiana, Michigan,
Minnesota, Mississippi, Missouri,
Nebraska, Nevada, New Jersey,
New Mexico, New York, North
Carolina, North Dakota, Ohio,
Oklahoma, South Carolina,
South Dakota, Tennessee,
Texas, Utah, Virginia, West
Virginia, Wisconsin, Wyoming),
American Samoa, Northern
Mariana Islands, Puerto Rico,
the Virgin Islands, and Guam
have implemented HIV case
surveillance, using the same
confidential system for name-based
case reporting for HIV
infection and AIDS.
Pennsylvania implemented
name-based reporting in areas
outside the city of Philadelphia.
Connecticut implemented
mandatory HIV reporting in
January 2002. For adults and
adolescents 13 years of age and
older, reporting is by name or
code (if patients or physicians
prefer this method). For children
< 13 years of age and for
persons who are co-infected with
tuberculosis, reporting is by
name. New Hampshire allows
HIV cases to be reported with or
without a name. Five states use
names to initiate case reports
and then convert to a code
(Delaware, Maine, Montana,
Oregon, Washington), and 10
areas are using a coded
identifier rather than patient
name to report HIV cases
(California, Hawaii, Illinois,
Kentucky, Maryland,
Massachusetts, Rhode Island,
Vermont, and the District of
Columbia). |
| Behavioral
surveillance |
Data on behaviors that are relevant to HIV
prevention, transmission, and medical care
are available from a variety of sources,
including general population surveys,
surveys of populations at risk for HIV, and
surveys of persons with HIV or AIDS.
Behavioral data include
- patterns of, or deterrents to, HIV testing
- substance use and needle sharing
- sexual behavior, including unprotected
sex
- sexual orientation
- health-care-seeking behavior
- adherence to prescribed antiretroviral
therapies
Examples: Supplement to HIV/AIDS
Surveillance; HIV Testing Survey;
Behavioral Risk Factor Surveillance
System; Young Men’s Survey; Survey of
HIV Disease and Care Project; Monitoring
Trends in Prevalence of STDs, TB, and HIV
Risk Behaviors Among Men Who Have Sex
with Men Project; Gonococcal Isolate
Surveillance Project; CDC HIV Behavioral
Surveys; Project One; and the Context of
HIV Infection Project |
Refer to
Appendix A to locate
sources of behavioral data in
your service area. |
| Clinical data |
Clinical data refer to information on the
condition(s) of persons with HIV or AIDS.
Clinical information is collected so as to
understand
- disease status at the time of diagnosis
and later progression (e.g., CD4+ cell
count, viral load, opportunistic
infections)
- type of medical care received
- prescription of antiretroviral therapy
- type of therapy received
Patient surveys collect data on adherence
to therapy and health-care-seeking
behavior. Depending on the source, clinical
data may represent all cases of reported
HIV and AIDS or only a fraction. Because
clinical data rely on the extent of
documentation in a medical record and an
ability to locate the record, they may be
incomplete.
Examples: Adult /Adolescent Spectrum of
Disease Project, Survey of HIV Disease and
Care Project, AIDS Progression Study, HIV
Outpatient Study, and other locally available
cohort data |
Refer to
Appendix A to locate
sources of clinical data in your
service area. |
| Demographic
data |
Demographic data are used to describe
social characteristics (e.g., gender, stage of
life, and race/ethnicity) of persons in the
service area. |
Available for state and
metropolitan areas from the
Bureau of the Census. Also,
states maintain census centers. |
| Hepatitis B and
C surveillance |
Data on hepatitis B and C virus (HBV, HCV)
infections may represent markers for needle
sharing and sexual behaviors, which can be risk factors for HIV transmission. Data on
hepatitis B and C are used to
- predict the likelihood and rate of spread
of viral hepatitis and HIV infections in a
community
- monitor trends
- identify needs for HIV prevention and
care services
Acute hepatitis B and C (i.e., clinical illness
with laboratory confirmation) is reportable in
all states; however, because of
underreporting and asymptomatic
infections, data are likely to be incomplete.
More than 40 states have registries for HBV
and HCV infection, and most have
laboratory reporting laws requiring reporting
of positive serologic test results for HBV
and HCV infection. Although serologic
markers for HBV infection can distinguish
between acute and chronic infection,
laboratory reports of positive HCV-antibody
results cannot differentiate newly acquired
infections from chronic or resolved
infections, making it difficult to monitor
disease trends for HCV. In addition, many
registries are relatively new, and their
usefulness has not been evaluated. |
State health department and
CDC staff. The quantity and the
quality of surveillance data differ between states. Refer to CDC’s
National Notifiable Disease
Surveillance System (soon to
become the National Electronic
Disease Surveillance System)
and the CDC Division of Viral
Hepatitis.
Reference: CDC. Guidelines for
Viral Hepatitis Surveillance and
Case Management. Atlanta: CDC; 2002. |
| Qualitative methods |
Qualitative methods are used to obtain data
through observations, interviews, discussion groups, focus
groups, and analysis of social networks. Example: Rapid
Assessment Response and Evaluation project |
Health department staff and local
community researchers often
use qualitative methods to
conduct research. Planning
group members may also be
aware of local studies.
Additional information can be
obtained from the
University of
Texas–Southwestern. |
| Ryan White
CARE Act data
reports |
The CARE Act data report (CADR) is a form
used to collect information annually from
grantees and service providers funded under
Titles I, II, III, or IV of the Ryan White CARE
Act. The CADR collects general information
on provider and program characteristics,
including the types of organizations providing
services (such as ownership status), sources
of revenue, expenditures, and paid and
volunteer staff. Additionally, the CADR is
used to collect aggregate demographic
information from which duplicates have been
removed (e.g., gender, race, age, HIV
exposure category) on total counts of clients
served by each provider as well as health
insurance coverage and utilization data about medical and support services.
The CADR is the only source of Ryan White
CARE Act data that is available in all states
and eligible metropolitan areas (EMAs). It
provides demographic information and
service utilization data on all Ryan White
CARE Act clients. In some areas, Title I or
Title II grantees have access to
unduplicated data across an entire EMA or
state. Because it is a summary report by
provider, the CADR cannot be used to
generate demographic cross-tabulations. |
Available in all 50 states and all
51 EMAs. Obtain these data
from local Ryan White Title I or
Title II grantees. |
| Sexually
transmitted
disease (STD)
surveillance |
These data are used in reports of notifiable
STDs such as syphilis, gonorrhea,
chancroid, and chlamydia. Use STD
surveillance data to obtain the number of
cases and incidence of specific STDs.
Demographic and clinical data are available
from STD surveillance data. They may
serve as a surrogate marker for unsafe
sexual practices in a specific risk
population. STDs are reportable in all 50
states and US territories. Despite
widespread availability, reporting of STDs
from private-sector providers may be less
complete. Although STDs are the result of
unsafe sexual behavior, STDs are not
necessarily good predictors of HIV infection. |
Available in all 50 states and US
territories. Contact the STD
program manager in your service
area for information. |
| Socioeconomic
data |
Surveys and other data collected from
community-based organizations, AIDS
service organizations, universities, and
special studies. Includes recurring surveys
in at-risk populations. |
Local researchers and
universities from the
Bureau of the Census and the
Bureau of Labor Statistics.
Additionally, states maintain census and labor statistics
centers. |
| Substance
abuse data |
Substance abuse data are obtained from
population-based surveys, medical
examiner records, correctional facilities, law
enforcement agencies, and drug treatment
centers. These sources describe the
patterns, prevalence, and consequences of
drug use in the general population and
specific populations. |
National Institutes of Health;
Substance Abuse
and Mental Health Services
Administration
for
information from drug-use
surveys and data on treatment
and drug abuse; National
Institute of Justice for
drug abuse among persons who
have been arrested |
| Tuberculosis
surveillance |
All 50 states, the District of Columbia, New
York City, Puerto Rico, and other US
jurisdictions in the Pacific and Caribbean
report tuberculosis (TB) cases to CDC on a
standard case report form. In 1993, in
conjunction with state and local health
departments, CDC implemented an
expanded surveillance system to collect
additional data to
- better monitor and target groups at risk
for TB
- estimate and follow the extent of drug resistant
TB
- evaluate outcomes of TB cases
Although information on HIV status among
reported TB cases is available, it may not
be complete because of
- confidentiality concerns that limit the
exchange of data between TB and
HIV/AIDS programs
- local or state laws and regulations that
prohibit the HIV/AIDS program and the
TB program from sharing information
about patients
- reluctance of health care providers to
report HIV test results to the TB
surveillance program staff
- a lack of counseling and HIV testing for
some TB patients
|
Available in all 50 states and US
territories. Contact the TB
program manager in your service
area for information. |
| Vital records |
Vital records contain information, as
stipulated by state statutes, on all births and
deaths in the 50 US states, the District of
Columbia, and US territories. For example,
death records include
- the cause of death according to the
rules of the National Center for Health
Statistics and the International
Classification of Diseases (ICD-9 or
ICD-10)
- date of death
- demographics of the deceased
|
All states maintain registries of
deaths. Contact the State Vital
Records Registrar. |
Go
to Chapter 2, Section 5
|
